Müller Weiss disease (MWD) is characterized by lateral navicular necrosis which is associated with a varus alignment of the subtalar joint, varying degrees of arthritis of the talonavicular-cuneiform joints and a paradoxical flatfoot deformity in advanced cases. Although arthrodesis of the hindfoot is commonly used, we present the results of a previously unreported method of treatment using a calcaneus osteotomy incorporating a wedge and lateral translation. Fourteen patients with MWD who were treated with a calcaneus osteotomy were retrospectively reviewed. There were seven females and seven males with an average age of 56 years (range 33–79), and included one grade 5, five grade 4, four grade 3 and four grade 2 patients. Patients had been symptomatic for an average of eleven years (range 1–14), and all underwent initial conservative treatment with an orthotic support that posted the heel into valgus. The primary indication for surgery was a limited but positive response to the use of the orthotic support, and a desire to avoid an arthrodesis of the hindfoot. Results. Patients were followed for an average of three years following the procedure (range 1 – 7 years). Patients rated their pain on a visual analogue pain scale as an average of 8 (range 6–9) prior to surgery and an average of 2 postoperatively (range 0–4). The AOFAS scores improved from a mean of 29 (range 25 – 35) preoperatively to a mean of 79 (range 75–88) postoperatively. Hindfoot range of motion remained and the extent of arthritis of the navicular complex was unchanged. No patient has since required an arthrodesis. Since the majority of MWD patients respond to an orthotic support which changes the load of the hindfoot and forefoot, we believed that patients would respond positively to a calcaneal osteotomy as an alternative treatment

Treatment of comminuted intraarticular calcaneal fractures remains controversial and challenging. Anatomic reduction with stable fixation has demonstrated better outcomes than nonoperative treatment of displaced intraarticular fractures involving the posterior facet and anterior calcaneocuboid joint (CCJ) articulating surface of the calcaneus. The aim of this study was to investigate the biomechanical performance of three different methods for fixation of comminuted intraarticular calcaneal fractures. Comminuted calcaneal fractures, including Sanders III-AB fracture of the posterior facet and Kinner II-B fracture of the CCJ articulating calcaneal surface, were simulated in 18 fresh-frozen human cadaveric lower legs by means of osteotomies. The ankle joint, medial soft tissues and midtarsal bones along with the ligaments were preserved. The specimens were randomized according to their bone mineral density to 3 groups for fixation with either (1) 2.7 mm variable-angle locking anterolateral calcaneal plate in combination with one 4.5 mm and one 6.5 mm cannulated screw (Group 1), (2) 2.7 mm variable-angle locking lateral calcaneal plate (Group 2), or (3) interlocking calcaneal nail with 3.5 mm screws in combination with 3 separate 4.0 mm cannulated screws (Group 3). All specimens were biomechanically tested until failure under axial loading with the foot in simulated midstance position. Each test commenced with an initial quasi-static compression ramp from 50 N to 200 N, followed by progressively increasing cyclic loading at 2Hz. Starting from 200 N, the peak load of each cycle increased at a rate of 0.2 N/cycle. Interfragmentary movements were captured by means of optical motion tracking. In addition, mediolateral X-rays were taken every 250 cycles with a triggered C-arm. Varus deformation between the tuber calcanei and lateral calcaneal fragments, plantar gapping between the anterior process and tuber fragments, displacement at the plantar aspect of the CCJ articular calcaneal surface, and Böhler angle were evaluated. Varus deformation of 10° was reached at significantly lower number of cycles in Group 2 compared to Group 1 and Group 3 (P ≤ 0.017). Both cycles to 10° plantar gapping and 2 mm displacement at the CCJ articular calcaneal surface revealed no significant differences between the groups (P ≥ 0.773). Böhler angle after 5000 cycles (1200 N peak load) had significantly bigger decrease in Group 2 compared to both other groups (P ≤ 0.020). From biomechanical perspective, treatment of comminuted intraarticular calcaneal fractures using variable-angle locked plate with additional longitudinal screws or interlocked nail in combination with separate transversal screws seems to provide superior stability as opposed to variable-angle locked plating only

Aims

This study was designed to characterize the recurrence incidence and risk factors of antibiotic-loaded cement spacer (ALCS) for definitive bone defect treatment in limb osteomyelitis.

Aims

Surgical treatment of young femoral neck fractures often requires an open approach to achieve an anatomical reduction. The application of a calcar plate has recently been described to aid in femoral neck fracture reduction and to augment fixation. However, application of a plate may potentially compromise the regional vascularity of the femoral head and neck. The purpose of this study was to investigate the effect of calcar femoral neck plating on the vascularity of the femoral head and neck.

Abstract. Objectives. The fidelity of a 3D model created using image segmentation must be precisely quantified and evaluated for the model to be trusted for use in subsequent biomechanical studies such as finite element analysis. The bones within the ankle joint vary significantly in size and shape. The purpose of this study was to test the hypothesis that the accuracy and reliability of a segmented bone geometry is independent of the particular bone being measured. Methods. Computed tomography (CT) scan data (slice thickness 1 mm, pixel size 808±7 µm) from three anonymous patients was used for the development of the ankle geometries (consisting of the tibia, fibula, talus, calcaneus, and navicular bones) using Simpleware Scan IP software (Synopsys, Exeter, UK). Each CT scan was segmented 4 times by an inexperienced undergraduate, resulting in a total of 12 geometry assemblies. An experienced researcher segmented each scan once, and this was used as the ‘gold standard’ to quantify the accuracy. The solid bone geometries were imported into CAD software (Inventor 2023, Autodesk, CA, USA) for measurement of the surface area and volume of each bone, and the distances between bones (tibia to talus, talus to navicular, talus to calcaneus, and tibia to fibula) were carried out. The intra-class coefficient (ICC) was used to assess intra-observer reliability. Bland Altman plots were employed as a statistical measure for criteria validity (accuracy) [1]. Results. The average ICC score was 0.93, which is regarded as a high reliability score for an inexperienced user. The talus to navicular and talus to tibia separations, which had the smallest distances, showed a slight decrease in reliability and this was observed for all separations shorter than 2 mm. According to the Bland-Altman plots, more than 95% of the data points were inside the borders of agreement, which is an excellent indication of accuracy. The bias percentage (average error percentage) varied between 1% and 4% and was constant across all parameters, with the proportion rising for short distance separations. Conclusions. The current study demonstrates that an inexperienced undergraduate, with access to software manuals, can segment an ankle CT scan with excellent reliability. The present study also concluded that all five bones were segmented with high levels of accuracy, and this was not influenced by bone volume or type. The only factor found to influence the reliability was the magnitude of distance between bones, where if this was smaller than 2 mm it reduced the reliability, indicating the influence of CT scan resolution on the segmentation reliability. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Abstract. Objectives. This abstract provides an update on the Open Ankle Models being developed at the University of Bath. The goal of this project is to create three fully open-source finite element (FE) ankle models, including bones, ligaments, and cartilages, appropriate musculoskeletal loading and boundary conditions, and heterogeneous material property distribution for a standardised representation of ankle biomechanics and pre-clinical ankle joint analysis. Methods. A computed tomography (CT) scan data (pixel size of 0.815 mm, and slice thickness of 1 mm) was used to develop the 3D geometry of the bones (tibia, talus, calcaneus, fibula, and navicular). Each bone was given the properties of a heterogeneous elastic material based on the CT greyscale. The density values for each bone element were calculated using a linear empirical relation, ρ= 0.0405 + (0.000918) HU and then power law equations were utilised to get the Young's Modulus value for each bone element [1]. At the bone junction, a thickness of cartilage ranging from 0.5–1 mm, and was modelled as a linear material (E=10 MPa, ν=0.4 [2]). All ligament insertions and positions were represented by four parallel spring elements, and the ligament stiffness and material attributes were applied in accordance with the published literature [2]. The ankle model was subjected to static loading (balance standing position). Four noded tetrahedral elements were used for the discretization of bones and cartilages. All degrees of freedom were restricted at the proximal ends of the tibia and fibula. The ground reaction forces were applied at the underneath of the calcaneus bone. The interaction between the cartilages and bones was modelled using an augmented contact algorithm with a sliding elastic contact between each cartilage. A tied elastic contact was used between the cartilages and the bone. FEbio 2.1.0 (University of Utah, USA) was used to construct the open-source ankle model. Results. When the double-legged stance phase loading condition was taken into consideration, stress at the antero-medial tibial wall (ranged from 1 to 7 MPa) was found to be similar to the prior work [2], indicating bulk of the load transfer was through this region. The maximum principal strain was predicted at the different regions on bones around the ankle joint. The proximal surface of the talus, and tibial distal surface were shown to have the highest maximum principal strains followed by antero-medial walls of the tibia bone, at the proximal location. Conclusions. The present open 3D FE model of the ankle will assist researchers in better understanding ankle biomechanics, precisely predicting load transfer, and examining the ankle to address unmet clinical needs for this joint. The results of the current investigation are realistic in terms of load transfer and stress-strain distribution across the ankle joint and well comparable to those reported in the literature [2]. However, sensitivity and ankle instability simulations will be performed in future work to investigate the model's reliability and robustness. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Objective. The objective of this study was to evaluate the rotation and translation of each joint in the hindfoot and compare the load response in healthy feet with that in stage II posterior tibial tendon dysfunction (PTTD) flatfoot by analysing the reconstructive three-dimensional (3D) computed tomography (CT) image data during simulated weight-bearing. . Methods. CT scans of 15 healthy feet and 15 feet with stage II PTTD flatfoot were taken first in a non-weight-bearing condition, followed by a simulated full-body weight-bearing condition. The images of the hindfoot bones were reconstructed into 3D models. The ‘twice registration’ method in three planes was used to calculate the position of the talus relative to the calcaneus in the talocalcaneal joint, the navicular relative to the talus in talonavicular joint, and the cuboid relative to the calcaneus in the calcaneocuboid joint. Results. From non- to full-body-weight-bearing condition, the difference in the talus position relative to the calcaneus in the talocalcaneal joint was 0.6° more dorsiflexed (p = 0.032), 1.4° more everted (p = 0.026), 0.9 mm more anterior (p = 0.031) and 1.0 mm more proximal (p = 0.004) in stage II PTTD flatfoot compared with that in a healthy foot. The navicular position difference relative to the talus in the talonavicular joint was 3° more everted (p = 0.012), 1.3 mm more lateral (p = 0.024), 0.8 mm more anterior (p = 0.037) and 2.1 mm more proximal (p = 0.017). The cuboid position difference relative to the calcaneus in the calcaneocuboid joint did not change significantly in rotation and translation (all p ≥ 0.08). . Conclusion. Referring to a previous study regarding both the cadaveric foot and the live foot, joint instability occurred in the hindfoot in simulated weight-bearing condition in patients with stage II PTTD flatfoot. The method used in this study might be applied to clinical analysis of the aetiology and evolution of PTTD flatfoot, and may inform biomechanical analyses of the effects of foot surgery in the future. Cite this article: Bone Joint Res 2013;2:255–63

The aim of this study was to evaluate the relationship between the location of the insertion point of the AT into the posterior aspect of the calcaneus and the PF. Two hundred and two feet were evaluated from MRI scans. Ninety-seven women and one hundred and five men with a mean age of 40.15±18.58 were included in this study. Two independent investigators measured the horizontal distance from the most anterior point of the calcaneus to the most posterior part of the PF (A), including the horizontal length of the calcaneus (B). Moreover, distance between the most inferior point of the calcaneus and the most inferior part of the AT insertion into the calcaneus (C) and height of the posterior aspect of the calcaneus (D) were measured. Patients were divided into three groups based on age (I - patients younger than 18, II − 18–65, III - older than 65The all obtained mean values showed high sexual dimorphism between genders. However, when standardized ratios were compared, no statistically significant sexual differences were noted (p>0.05). Although previous studies have reported a correlation between the PF, age and gender, this correlation was not found in our study. Based on the obtained results, this study concludes that age and sex do not influence the morphology of the PF. However, aging strongly affects the location of the AT insertion point. Therefore, we believe this is the key factor which influence the relationship between the AT and PF

Insertional Achilles tendinitis with considerable degeneration that failed non-operative treatment typically requires tendon debridement and reattachment to bone. It is common practice for tendons to be reattached back with anchor sutures, but this poses a challenge to patients who are not able to afford them. Bony anchorage of tendons may be performed by passing sutures through tunnels, but the strength of repair compared to by using anchors is not known. We investigated the load at clinical and catastrophic failure of these two methods of reattachment. Sixteen paired Achilles tendons along with the calcaneus were harvested from eight fresh frozen cadavers. Paired randomization was done. For the anchor suture group, two 5’0 anchors with polyethylene #2 sutures were used for reattachment whereas for the suture only group, tendons were reattached to bone using braided polyester #2 sutures via two bony tunnels. All samples were mounted on a materials testing system and preloaded at 50N for 60sec before load to failure at a rate of 1mm/sec. With the assumption that preloading has removed tendon crimp and any subsequent extension is a result of gapping at the repair site, loads at 5mm, 10mm, 15mm, and 20mm of extension were noted as well as the maximal load at failure. We found higher loads were needed to cause an extension of 5 to 20mm in the suture only group compared to the anchor suture group but these data were not significant. On the other hand, the anchor suture group required higher loads before catastrophic failure occurred compared to the suture only group, but this again is not significant. We conclude that suture only reattachment of the Achilles tendon is comparable in strength with anchor suture reattachment, and this method of reattachment can be considered for patients who do not have access to anchor sutures

Aims. Management of intra-articular calcaneal fractures remains a debated topic in orthopaedics, with operative fixation often held in reserve due to concerns regarding perioperative morbidity and potential complications. The purpose of this study was to identify the characteristics of patients who developed surgical complications to inform the future stratification of patients best suited to operative treatment for intra-articular calcaneal fractures and those in whom surgery was highly likely to produce an equivocal functional outcome with potential post-operative complications. Methods. All patients who underwent open reduction and internal fixation of calcaneal fractures utilizing the Sinus Tarsi approach between March 2014 and July 2018 were identified using theatre records. Patient imaging was used to assess pre- and post-operative fracture geometry with Computed Tomography (CT) used for pre-operative planning. Each patient's clinical presentation was established through retrospective analysis of medical records. Patients provided verbal consent to participation and patient reported outcome measures were recorded using the Maryland Foot Score. Results. Fifty-eight intra-articular calcaneal fractures (fifty-three patients including five bilateral, mean age = 46.91 years) were included. Forty-nine patients were injured as a result of a fall from a height (92.4%). Mean time from presentation to surgery was 3.23 days (range 0–21). Mean Maryland Foot score was found to be 77.6 (+/− 16.22) in forty-five patients. Five patients (9.4%) had wound complications; two superficial (3.7%) and three deep (5.6%). Conclusion. Intra-articular fractures of the calcaneus should be considered for surgical intervention in order to improve long-term functional outcomes. The Sinus Tarsi approach provides the potential to decrease the operative complication rate whilst maintaining adequate fixation, however, the decision to surgically manage these fractures should be carefully balanced against the risk of post-operative complications. This increased risk of complication associated with smoking may tip the balance against benefit from surgical management

Background. Surgical management of calcaneus fractures is demanding and has a high risk of wound complications. Traditionally these fractures are managed with splinting until swelling has subsided. We describe a novel protocol for the management of displaced intra-articular calcaneus fractures utilising a temporizing external fixator and staged conversion to plate fixation through a sinus tarsi approach. The goal of this technique is to allow for earlier treatment with open reduction and internal fixation, minimise the amount of manipulation required at the time of definitive fixation and reduce the wound complication rate seen with the extensile approach. Methods. The records of patients with displaced calcaneus fractures from 2010–2014 were retrospectively reviewed. A total of 10 patients with 12 calcaneus fractures were treated with this protocol. All patients underwent ankle-spanning medial external fixation within 48 hours of injury. Patients underwent conversion to open plate fixation through a sinus tarsi approach when skin turgor had returned to normal. Time to surgery, infection rate, wound complications, radiographic alignment, and time to radiographic union were recorded. Results. The average Bohler's angle improved from 13.2 (range −2 to 34) degrees preoperatively to 34.3 (range 26 to 42) degrees postoperatively. The average time from external fixation to conversion to internal fixation was 4.8 (range 3 to 7) days. There were no immediate post-surgical complications. The average time to weight bearing was 8.5 weeks. The average time to radiographic union was 9.5 (range 8 to 12) weeks. There were no infections or wound complications at the time of last follow-up. Conclusions. Early temporizing external fixation for the acute management of displaced calcaneus fractures is a safe and effective method to reduce and stabilise the foot and may decrease the time to definitive fixation. In our series there were no complications related to the use of the external fixator. Level of Evidence. IV Retrospective case series

Background. A calcaneal medial osteotomy (CMO) is a surgical procedure frequently performed to correct a valgus alignment of the hindfoot. However currently little is known on its accurate influence on hindfoot alignment (HA). Aim. To assess the influence of a CMO on HA in both 2D and 3D measurements using weightbearing CT (WBCT). Methods. Twelve patients with a mean age of 49,4 years (range 18–67yrs) were prospectively included. Indications for surgical correction by a CMO with a solitary translation of the calcaneus consisted of an adult acquired flat foot stage II (N=10) and a talocalcaneal coalition (N=2). Fixation of the osteotomy was performed either using a step plate or double screw. A WBCT was obtained pre- and post-operative. HA was assessed by an angle between the anatomical tibia axis and the axis connecting the inferior calcaneus point and the middle of the talus in the coronal plane (HA. 2D. ) using Curvebeam® software. The tibia in the HA was separately assessed by the anatomical tibia axis (TA. X 2D. ). The same method was translated in 3D using 3-Matic® software with a Cartesian coordinate system originating in the inferior point of the calcaneus (HA. 3D. and TA. x 3D. ). Results. Both the mean pre-op HA. 2D. =12.8°± 4.5 and HA. 3D. =21.1°± 8.4 of valgus improved significantly post-operatively to a HA. 2D. =4.2°±4.5 and a HA. 3D. =11,9°± 6.1 (P < 0.001). Additionally, the mean pre-op TA. X 2D. = 4°± 2.6 and TA. X 3D. = 7,2 °± 3.2 showed a significant improvement to a TA. X 2D. = 3.1°± 2.7 and a TA. X 3D. = 6.1 °± 3.4 post-operatively (P < 0.05). The inter-rater reliability of the 2D measurement method with a mean ICC. HA2D. =0.74 and a mean ICC. TA2D. = 0.77 showed to be lower when compared to the 3D measurement method with a mean ICC. HA3D. =0.94 and a mean ICC. TA3D. =0.89. Conclusion. This study shows an effective correction of the valgus position from the calcaneus measured both in 2D and 3D when using a surgical CMO. The novelty is the marked influence on the tibia, which could now be accurately assessed using a weightbearing CT and additional 3D measurements. This resulted in 10% of the achieved HA correction, when analyzed both in 2D and 3D. This information could be of use when performing a pre-operative planning of a hindfoot deformity

The flat foot is a frequent deformity in children and results in various levels of functional alterations. A diagnosis based on foot morphology is not sufficient to define the therapeutic approach. In fact, the degree of severity of the deformity and the effects of treatments require careful functional assessment. In case of functional flatfoot, subtalar arthroereisis is the surgical treatment of choice. The aim of this study is to evaluate and compare the functional outcomes of two different bioabsorbable implants designed for subtalar arthroereisis in childhood severe flat foot by means of thorough gait analysis. Ten children (11.3 ± 1.6 yrs, 19.7 ± 2.8 BMI) were operated for flat foot correction [1,2] in both feet, one with the calcaneo-stop method, i.e. a screw implanted into the calcaneus, the other with an endoprosthesis implanted into the sinus-tarsi. Gait analysis was performed pre- and 24 month post-operatively using a 8-camera motion system (Vicon, UK) and a surface EMG system (Cometa, Italy) to detect muscular activation of the main lower limb muscles. A combination of established protocols, for lower limb [3] and multi-segment foot [4] kinematic analysis, was used to calculate joint rotations and moments during three level walking trials for each patient. At the foot, the tibio-talar, Chopart, Lisfranc, 1. st. metatarso-phalangeal joints were tracked in three-dimensions, together with the medial longitudinal arch. Significant differences in standard X-ray measurements were observed between pre- and post-op, but not between the two treatment groups. Analysis of the kinematic variables revealed functional improvements after surgery. In particular, a reduction of eversion between the shank and calcaneus (about 15° on average) and a reduction of inversion between metatarsus and calcaneus (about 18° on average) were detected between pre- and post-operatively after both treatments. Activation of the main plantar/dorsiflexor muscles was similar at both pre- and post-op assessments with both implants. The combined lower limb and multi-segment foot kinematic analyses were found adequate to provide accurate functional assessment of the feet and of the lower limbs. Both surgical treatments restored nearly normal kinematics of the foot and of the lower limb joints, associated also to a physiologic muscular activation

Introduction: Preoperative use of tomodensitometry is a common practice when assessing fractures with intraarticular involvement, helping to determine the most appropriate surgical approach according to the lesions observed. To date, during the surgical procedure itself, radiographical or fluoroscopic controls still largely rely on two dimensions X rays. We assessed the possible benefits of intraoperative tridimensional reconstructions using mobile isocentric fluoroscopy (iso-C-3D) after one year of use. Material and Methods: All the procedures where intra-operative tridimensional fluoroscopy was used were assessed prospectively for one year. The type of osteosynthesis as well as specific modalities of installation and therapeutic measures driven from analysis of the images were analyzed. Results: During the first year of use, intraoperative tridimensional reconstruction had been carried out in 48 procedures in 47 patients. The region involved was calcaneus 13 times, thoracolumbar spine 12 times, acetabulum 11 times, tibial condyles 9 times, axis 2 times and pelvis one time. Installation was the same than usually performed in the cases of calcaneus and axis osteosynthesis. For the other localisations, obtention of good quality images was facilitated through the use of a carbon table for spine and osteosynthesis of the tibial condyles, and through the use of a carbon traction table for acetabular or pelvic fractures. Intraoperative tridimensional reconstruction allowed to check for freedom of the vertebral canal after reduction and osteosynthesis of the spine. in the cases of fracture of the calcaneus, reduction of one thalamic fragment was improved in one case and one intraarticular screw could be changed in another case. In the case of acetabular surgery, one screw stabilizing the posterior wall was found intraarticular on tridimensional reconstruction and could be changed before closure. Discussion: Intraoperative tridimensional reconstruction, during its first year of use, allowed to avoid 3 early reinterventions (for 2 calcaneus and one acetabulum). Accurate interpretation of standard plain X ray in these two localizations is difficult because of the spherical shape of the hip joint and because good quality imaging, especially the retrotibial view, is hardly obtained intraoperatively in fractures of the cacaneus. When using tridemensional reconstructions, acquisition of good quality images has to be anticipated during the installation of the patient, limiting any interfereces with metallic supports to a minimum. Conclusion: the results obtained over the first year of use of intraoperative tridimensional reconstructions with the ISO-C-3D encouraged the authors to generalize its use when performing osteosynthesis of the acetabulum or calcaneus as well as percutaneus osteosynthesis of articular fractures

Purpose. The goal of Total Ankle Arthroplasty (TAA) is to relieve pain and restore healthy function of the intact ankle. Restoring intact ankle kinematics is an important step in restoring normal function to the joint. Previous robotic laxity testing and functional activity simulation showed the intact and implanted motion of the tibia relative to the calcaneus is similar. However there is limited data on the tibiotalar joint in either the intact or implanted state. This current study compares modern anatomically designed TAA to intact tibiotalar motion. Method. A robotic testing system including a 6 DOF load cell (AMTI, Waltham, MA) was used to evaluate a simulated functional activity before and after implantation of a modern anatomically designed TAA (Figure 1). An experienced foot and ankle surgeon performed TAA on five fresh-frozen cadaveric specimens. The specimen tibia and fibula were potted and affixed to the robot arm (KUKA Robotics Inc., Augsburg, Germany) while the calcaneus was secured to a fixed pedestal (Figure 1). Passive reflective motion capture arrays were fixed to the tibia and talus and a portable coordinate measuring machine (Hexagon Metrology Group, Stockholm, Sweden) established the location of the markers relative to anatomical landmarks palpated on the tibia. A four camera motion capture system (The Motion Monitor, Innovative Sports Training, Chicago, IL) recorded the movement of the tibia and talus. The tibia was rotated from 30 degrees plantar flexion to 15 degrees dorsiflexion to simulate motions during the stance phase of gait. At each flexion angle the robot found the orientation which zeroed all forces and torques except compressive force, which was either 44N or 200N. Results. Preliminary data indicates the tibiotalar motion of the TAA is similar to the intact ankle. The pattern and magnitude of tibiotalar translations and rotations are similar between the intact and implanted states for both 44N and 200N compressive loads (Figure 2). The most variation occurs with internal-external rotation. Increased translation especially in the anterior-posterior directions was observed in plantarflexion while the mediolateral translation remained relatively centered moving less than a millimeter. The intact talus with respect to the calcaneus had less than 3 degrees of rotation over the whole arc of ankle flexion (Figure 3). The angular motion of the implanted talus was similar in pattern to the intact talus, however there were offsets in all three angular directions which changed depending on the loading (Figure 3). This indicates that most of the motion that occurs between the intact tibial calcaneal complex occurs in the tibiotalar joint. Conclusion. Although more investigation is required, this study adds to the limited available tibiotalar kinematic data. This current study suggests the anatomical TAA design allows the tibiotalar joint to behave in similar way to the intact tibiotalar joint. Restoring intact kinematics is an important step in restoring normal function to the joint. For figures/tables, please contact authors directly.

Aim. The aim of this work was to evaluate, via foot and ankle TC scans, the outcomes of the use of a bone substitute (CERAMENT|™G) and the growth of native bone in the treatment of osteomyelitis (OM) of the diabetic foot. Method. In nine patients from July 2014 to December 2016 we used a Calcium Sulphate Hemihydrate + Hydroxyapatite + Gentamicin Sulfate (CSH + HA + GS) compound to fill resected bone voids following surgical intervention in OM diabetic foot cases. Of these nine patients, three were female and six were male and their ages were between 49 and 72 years. Four patients had hindfoot involvement and underwent partial calcanectomy. Two patients presented a rocker-bottom Charcot foot pattern III according to Sanders and Frykberg's classification and were treated with esostectomy of the symptomatic bony prominence of the midfoot. One patient presented OM of the 3°, 4° and 5° metatarsal bones. One patient underwent partial resection of the midfoot and hindfoot with arthrodesis stabilised by an internal-external hybrid fixator. One patient with a Charcot foot pattern IV-V underwent partial talectomy and calcanectomy with arthrodesis stabilised by an internal-external hybrid fixator. In all these patients - after removal of the infected bone - we applied 10 to 20 ml CSH + HA + GS filling the residual spaces with the aim of stabilising the remaining bone fragments. The uniqueness of this product is that it induces native bone growth, while the synthetic bone disappears and antibiotic is released into the surrounding tissues. In March 2018, the above nine patients underwent foot and ankle TC scans to evaluate bone growth. Results. The first four patients showed new bone formation in the calcaneus. Two patients with previous midfoot destruction showed chaotic but stable bone formation. The patient with metatarsal OM showed partial bone healing with residual pseudoarthrosis. Both the two patients who underwent arthrodesis with hybrid fixators showed a plantigrade and stable foot even though a heel wound is still present in one of the patients. All patients except this one are now wearing suitable shoes as post-operative wounds have healed. The patient still with the heel wound is walking with an aircast brace. Conclusion. The TC scans have shown new bone formation sufficient to stabilise the foot and allow ambulation. In particular, very good results come from the filling of the calcaneus, probably due to the anatomy of the bone itself

Introduction: This study prospectively measured fifty consecutive patients who had the preoperative diagnosis of osteoarthritis undergoing total knee arthroplasty (TKA) to evaluate the change of the bone mineral density (BMD) of the calcaneus. Materials & Methods: Broadband ultrasound attenuation through the calcaneus was measured to assess the BMD of patients. The BMD was measured preoperatively and 1 month (M), 3M, 6M, 1 year, and 2 years after TKA. Results: The mean BUA at each stage was 47.1, 45.8, 46.7, 46.7, 47.8 and 53.1, respectively. During the first 6 months, the BUA declined inconsistently in most patients, but by 1 year, the BUA recovered to the initial BUA before surgery and by 2 years, the BUA increased than the initial BUA, although there ware not satisfactory different. Despite a predicted age-related loss of 4% during 2 years, 78% of the calcaneus on the operative side had BMD higher than preoperative levels and 85% had BMD that was within the expected 4% age-related loss. Discussion: These results indicated that TKA might contribute to decrease the age-related BMD loss. The increase with TKA in patient mobility and the increased heel loading may be a mechanism whereby the calcaneus BMD increases. Conclusion: It is very important for surgeons to recognize the objection beneficial effects of TKA in addition to pain relief

Aim. Chronic osteomyelitis of the calcaneus is a frequent problem in a population of diabetic patients, patients with neurologic disorders or bedridden patients with ulcers. Partial calcanectomy is an alternative option which avoid major amputation. The aim of this retrospective study was to determine the effectiveness of partial calcanectomy for treating chronic osteomyelitis of the calcaneux. Method. We conducted a retrospective review of patients who underwent in our department a partial calcanectomy between 2006 and 2015. All patients with a complete set of radiographs and adequate follow-up (minimum 2 years) were included. We reviewed these cases to determine healing rate, microbiological analysis, risk factors of failure (comorbidities), limb salvage rate and survival rate. We analyzed specifically the footwear and the functional subjective evaluation according to the LEFS score (Lower Extremity Functional Scale). Results. Twenty-four patients were included (24 foot). There were 17 men and the mean age was 65.2 years. The control of the infection and the healing was obtained in 15 cases. An additional surgery was required in 46% of the cases. A transtibial amputation has been realized in 9 cases because of uncontrolled infection. The existence of a preoperative vascular disease increased 5,9 times the risk of amputation after a partial calcanectomy (p=0,033). The type of germ was not related to the risk of recurrence. Soles were necessary for 60% of the patients with a successful partial calcanectomy (n=15). The average LEFS score was 51/80. Conclusion. The treatment of the chronic osteomyelitis of the calcaneus was a therapeutic challenge for these patients. The partial calcanectomy is a useful procedure for limb salvage, but the selection of patients must be rigorous. In our study, arteriopathic patients had a high risk of amputation after partial calcanectomy. When the healing is acquired, the patients were satisfied and presented a good function

When total ankle arthroplasty (TAA) is performed, although tibial osteotomy is instructed to be perpendicular to long axis of tibia, there is no established index for the talar bone corrective osteotomy. Then, we have been deciding the correction angle at the plan for adjustment of the loading axis through whole lower extremities. We studied 17 TAA cases with rheumatoid arthritis (RA). X-ray picture of hip to calcaneus view (hip joint to tip of the calcaneus) defined to show more approximated loading axis has been referred for the preoperative planning. Furthermore, the data of correction angle has been reflected to pre-designed custom-made surgical guide. If soft tissue balance was not acceptable, malleolar sliding osteotomy was added. The distance between the centre of ankle joint and the axis (preD) was measured (mm) preoperatively, and the distance between the centre of prosthesis and the axis (postD) was measured postoperatively. Next, the tilting angle between tibial and talar components (defined as the index of prosthesis edge loading) were measured with X-rays during standing. Tibio Calcaneal (TC) angle was also measured pre and postoperatively. TC angle was significantly improved from 8.3±6.0° to 3.5±3.6° postoperatively (P=0.028). PreD was 12.9±9.6mm, and that was significantly improved to 4.8±6.3mm (postD) (P=0.006). Within 17 cases, 8 cases showed 0–1mm of postD, 4 cases showed 1–5mm of postD, remaining 5 cases concomitant subtalar fusion with severe valgus and varus hindfoot deformity showed over 8mm of postD. All of the 12 cases showing within 5mm of postD indicated within 13mm of preD. The tilting angle between components was 0.17±0.37° postoperatively. Taken together, pre-designed corrective talar osteotomy based on preoperative planning using hip to calcaneus view was useful to adjust the mechanical axis for replaced ankle joint in RA cases. Furthermore, after surgery, the hip to calcaneus view was useful to evaluate post-operative mechanical axis of whole lower extremities

Purpose: Fractures of the calcaneus remain a significant clinical challenge. Little study has been done to investigate the potential benefit of bone graft in the treatment of these fractures. The purpose of this study is to compare the clinical outcome of calcaneus fractures treated with and without ICBG. Method: In an ongoing study at a Level I Trauma Center 45 patients with calcaneus fractures requiring operative management were enrolled in a prospective, randomized study. 24 patients were randomized to ORIF without graft (control) and 24 patients were randomized to ORIF with ICBG (study group). Demographic, intra-operative and long term clinical outcome data was collected. Outcome measures included pain scores, Creighton-Nebraska Foot Scores, time to weight bearing, return to work and wound complications. Results: The groups showed no differences in gender, age, mechanism of injury, fracture classification or time to surgery (avg. 12 days). Tscherne scores at presentation differed, with higher average scores in the control group. There were 2 open fractures in each group. The groups showed no statistically significant differences in any of the clinical outcome measures. There was no difference in pain scores (control mean 2.6 vs. study mean 4.1, p = 0.1), Creighton-Nebraska Scores (control 71 vs. study 55, p = 0.1), time to weight bearing (control 2.6 months vs. study 2.7 months, p = 0.9). At 6 months 38% of controls had returned to work (with 87% of those returning to the some occupation) while 39% of the study group returned to work (71% to same occupation). An overall wound complication rate of 27% was seen with 30% of controls and 24% of study patients exhibiting wound issues. Conclusion: In this prospective randomized study, patients treated with ORIF for calcaneus fractures showed no difference in clinical outcomes with or without the addition of ICBG. No clear benefit is demonstrated to warrant the additional operative time, pain and possible complications that have been previously documented to be associated with ICBG